Vulnerability-Lookup

EUVD-2026-309487

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 07:09

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

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{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T07:09:10.559984+00:00",
  "id": "EUVD-2026-309487"
}

CVE-2021-47010 (GCVE-0-2021-47010)

Vulnerability from cvelistv5 – Published: 2024-02-28 08:13 – Updated: 2026-05-11 13:46

Title

net: Only allow init netns to set default tcp cong to a restricted algo

Summary

In the Linux kernel, the following vulnerability has been resolved: net: Only allow init netns to set default tcp cong to a restricted algo tcp_set_default_congestion_control() is netns-safe in that it writes to &net->ipv4.tcp_congestion_control, but it also sets ca->flags |= TCP_CONG_NON_RESTRICTED which is not namespaced. This has the unintended side-effect of changing the global net.ipv4.tcp_allowed_congestion_control sysctl, despite the fact that it is read-only: 97684f0970f6 ("net: Make tcp_allowed_congestion_control readonly in non-init netns") Resolve this netns "leak" by only allowing the init netns to set the default algorithm to one that is restricted. This restriction could be removed if tcp_allowed_congestion_control were namespace-ified in the future. This bug was uncovered with https://github.com/JonathonReinhart/linux-netns-sysctl-verify

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-07-25 15:24 UTC

CWE

CWE-400 - Uncontrolled Resource Consumption

Assigner

Linux mitre root Scorecard

References

6 references

URL	Tags
https://git.kernel.org/stable/c/992de06308d9a9584…
https://git.kernel.org/stable/c/9884f745108f7d25b…
https://git.kernel.org/stable/c/6c1ea8bee75df8fe2…
https://git.kernel.org/stable/c/efe1532a6e1a8e3c3…
https://git.kernel.org/stable/c/e7d7bedd507bb732e…
https://git.kernel.org/stable/c/8d432592f30fcc34e…

Impacted products

3 products

Vendor	Product	Version
Linux	Linux	Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < 992de06308d9a9584d59b96d294ac676f924e437 (git) Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < 9884f745108f7d25b189bbcd6754e284fb29ab68 (git) Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < 6c1ea8bee75df8fe2184a50fcd0f70bf82986f42 (git) Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < efe1532a6e1a8e3c343d04fff510f0ed80328f9c (git) Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < e7d7bedd507bb732e600403b7a96f9fe48d0ca31 (git) Affected: 6670e152447732ba90626f36dfc015a13fbf150e , < 8d432592f30fcc34ef5a10aac4887b4897884493 (git)
Linux	Linux	Affected: 4.15 Unaffected: 0 , < 4.15 (semver) Unaffected: 4.19.191 , ≤ 4.19.* (semver) Unaffected: 5.4.119 , ≤ 5.4.* (semver) Unaffected: 5.10.37 , ≤ 5.10.* (semver) Unaffected: 5.11.21 , ≤ 5.11.* (semver) Unaffected: 5.12.4 , ≤ 5.12.* (semver) Unaffected: 5.13 , ≤ * (original_commit_for_fix)
linux	linux_kernel	Affected: 6670e1524477 , < 992de06308d9 (custom) Affected: 6670e1524477 , < 9884f745108f (custom) Affected: 6670e1524477 , < 6c1ea8bee75d (custom) Affected: 6670e1524477 , < efe1532a6e1a (custom) Affected: 6670e1524477 , < e7d7bedd507b (custom) Affected: 6670e1524477 , < 8d432592f30f (custom) Affected: 4.15 Unaffected: 0 , < 4.15 (custom) Unaffected: 4.19.191 , ≤ 4.20 (custom) Unaffected: 5.4.119 , ≤ 5.5 (custom) Unaffected: 5.10.37 , ≤ 5.11 (custom) Unaffected: 5.11.21 , ≤ 5.12 (custom) Unaffected: 5.12.4 , ≤ 5.13 (custom) Unaffected: 5.13 , ≤ * (custom) cpe:2.3:o:linux:linux_kernel:-:::::::*

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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EUVD-2026-309487

CVE-2021-47010 (GCVE-0-2021-47010)

Tags

Sightings

Nomenclature

Related by attack behaviour